Heat is one of the most energy forms emitted to atmosphere by industrial processes. Water is considered to be the best material to reduce heat energy since its available in nature in abundance and has the ability to absorb heat efficiently. Cooling towers are ideal alternatives to re-cool hot water instead of throwing it especially in places that lack natural water resources or when there are environmental precautions because water with high temperature would be harmful to the ecosystem when it recycled to natural resources such as rivers and lakes. Also, cooling towers considered economically feasible when using west water. This paper interests with hydraulic characteristics of a counter flow wet cooling tower which was investigated experimentally. The tower filled with splash packing with Zig-Zag pattern. Current study used treated waste water and focused fundamentally on the influence of air and water flow rates on hydraulic features of cooling tower for different access water temperatures. The dependency between pressure drop and the air and water flux was spotted. In this study, it found that within a certain ranges the pressure drop increases by 75% due to liquid flux and 70% due to air flux while pressure drop is not affected by changing temperature at all. Two empirical correlation had been founded for dry pressure drop (with R2=99.5%), and for wet pressure drop (with R2=98.13%).
The aim of this research is to investigation the optimization of the machining parameters (spindle speed, feed rate, depth of cut, diameter of cutter and number of flutes of cutter) of surface roughness for free-form surface of composite material (Aluminum 6061 reinforced boron carbide) by using HSS uncoated flat end mill cutters which are rare use of the free-form surface. Side milling (profile) is the method used in this study by CNC vertical milling machine. The purpose of using ANFIS to obtain the better prediction of surface roughness values and decreased of the error prediction value and get optimum machining parameters by using Taguchi method for the best surface roughness at spindle speed 4500 r.p.m, 920mm/rev feed rate, 0.6mm de
... Show MoreFinite element modeling of transient temperature distribution is used to understand physical phenomena occurring during the dwell (penetration) phase and moving of welding tool in friction stir welding (FSW) of 5mm plate made of 7020-T53 aluminum alloy at 1400rpm and 40mm/min.
Thermocouples are used in locations near to the pin and under shoulder surface to study the welding tool penetration in the workpiece in advance and retreate sides along welding line in three positions (penetrate (start welding) , mid, pullout (end welding)).
Numerical results of ANSYS 12.0 package are compared to experimental data including axial load measurements at different tool rotational speeds (710rpm.900rpm.1120rpm and 1400rpm) Based on the experiment
In this work, a test room was built in Baghdad city, with (2*1.5*1.5) m3 in dimensions, while the solar chimneys (SC) were designed with aspect ratio (ar) bigger than 12. Test room was supplied by many solar collectors; vertical single side of air pass with ar equals 25, and tilted 45o double side of air passes with ar equals 50 for each pass, both collectors consist of flat thermal energy storage box collector (TESB) that covered by transparent clear acrylic sheet, third type of collector is array of evacuated tubular collectors with thermosyphon in 45o instelled in the bottom of TESB of vertical SC. The TESB was
... Show MoreUniversity libraries seek to evaluate their performance in order to correct their path and adjust it in the right direction. Therefore, they use (performance indicators), which are a tool used by institutions to evaluate the weaknesses and strengths in their work and the reasons for failure to achieve some goals sometimes. They convert (goals, procedures and actions) into a formula that can be measured mathematically, which contributes to the library determining the gap between its current performance and what those libraries are supposed to be on, clarifying the path that the library is following, controlling the risks that may befall it, and thus enhancing the process of continuous improvement to avoid areas of failure and weakness becaus
... Show MoreObjective: The study deafs with nursing performance in the surgical wards in general hospital at
Baghdad city.
Methodology : A descriptive evaluation design using, observational method was carried out. Non
probability (purposive) sample of (151) nurses was selected for the study and comprised all nurses who
worked in general surgical wards in the four health sectors( Rusaffa , Al-Karkh, Al-Yarmok, Medical
city health sector) at time of collecting the data. A check list questionnaire was constructed by the
researcher for the purpose of the study; it is composed of (2) major parts, part (I) is concerned with
socio-demographic data and the second part is composed of two minor parts thev concerned with
availability of
Abstract
The cultural contrast is considered of the essential subjects in the field of administration of international businesses which have great and effective role for representation in one social system for the individuals have various belongings, and the nursing performance is considered an essential basic for health care, thus a discussion for two variables have done to formulate the intellectual frame for this research which are( the cultural contrast and the nursing performance). depended a questionnaire as a research tool by(90) he/ she nurses of the Iraqis and the arrivals( the
... Show MoreA plastic tubes used as absorber of active flat plate solar collector (FPSC) for heating water were studied numerically and experimentally. The set-up is located in Babylon (republic of Iraq) 43.80 East longitude and 32.30 North latitude with titled of 450 toward the south direction. The study involved three dimensions mathematical model for flat coil plastic absorber which solved by FLUENT-ANSYS-R.18 program. Experiments were conducted at outdoor conditions for clear days on January and February 2018 with various water volume flow rates namely (500, 750, 1000, 1250, and 1500 Liter per hour LPH) on each month for Reynolds number range of (1 x 104 to 5 x 104) th
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